Most modern military forces use energetic tracers based on technology that was developed in the early 1900s. Energetic tracer projectiles generate light through the use of energetic material imbedded in the rear of the projectile, similar to the effect of a burning road flare. Despite various technological advancements that have been made in tracers over the years since their introduction, energetic tracers nevertheless have several shortcomings. These shortcomings include:                1. The incendiary nature of energetic tracers makes them a fire hazard. The fires can be a safety hazard in training areas and can be an undesirable consequence in battle.        2. The tracers lose mass in flight, creating an inherent inaccuracy and lack of precision.        3. The material used for energetic tracers creates environmental and hazardous material problems.        4. The energetic tracers are difficult to manufacture.        5. Energetic tracers are bi-directional; meaning they can be seen by the shooter as well as the enemy.        
Conventional energetic tracers contain pyrotechnic material, typically in a cavity at their base. The pyrotechnic material is ignited by the burning of the energetic component of the cartridge and burns brightly during flight. The usual practice is to load energetic tracers into an ammunition belt at a ratio of one tracer bullet per four rounds in ground-based guns, and one tracer per every two or three rounds in aircraft guns. Energetic tracers can never be a totally reliable indicator of a gunner's aim because the energetic tracers have different aerodynamic properties and weights when compared to standard rounds that are being fired with the energetic tracers.
Because the material used to manufacture energetic tracers is pyrotechnic, energetic tracer ammunition must be produced in a production line separate from the standard ammunition production line. In order to accommodate the tracer material, the length of an energetic tracer bullet is typically longer than a standard bullet of the same caliber. The increased length also adds to the complexity of manufacture because the tracer bullet takes up additional space in the cartridge that would otherwise be used for the propellant in a non-tracer cartridge.
The standard cartridge is made up of four components: primer, case, gun powder, and bullet. FIGS. 1A and 1B show cut-away views for certain cartridges. The primer is installed in the rear of the case in a cavity known as the primer pocket. A small hole, roughly one-third the diameter of the primer and known as the flash hole, is located in the center of the primer pocket. The flash hole establishes communication between the primer pocket and the body of the case that contains the gun powder and bullet. A full metal jacket that encases the lead core of the bullet is also evident in FIGS. 1 and 2.
Manufacturing of ammunition has numerous hazards associated with it. When coupled with energetic tracer manufacturing the problems increase greatly. Storage of energetic tracer material, product quality control, and worker health are only some of the obvious problems. Primer material and gunpowder expose manufacturers to some risk of explosion and fire, but these materials are absolutely necessary for the manufacturing of energetic tracer ammunition. Energetic tracer material increases the hazard to military ammunition manufacture. A non-energetic material with tracer properties would reduce the manufacturing risk by removing the toxic and flammable energetic tracer material from the equation.
Another problem associated with conventional tracers is that they typically leave behind a narrow cloud of burning material that can be up to about a meter long. While this increases the visibility of the tracer to the shooter, it also makes the tracer visible to the target and unfriendly observers in the surrounding area. Further, conventional tracers have resulted in fires on training ranges, as well as in the field, where fires are caused by the continued burning of the pyrotechnic material upon impact within the target area.
There have been attempts to produce tracers without the shortcomings mentioned above. For example, U.S. Patent Application Publication No. 2004/0099173 teaches the use of a light emitting diode (LED) and capacitor, instead of a pyrotechnic material, in an attempt to decrease tracer visibility from the target and surrounding area. Likewise, U.S. Patent Application Publication No. 2005/0034627 teaches the use of an electronic light source in lieu of the use of a pyrotechnic material. However, such attempts still result in a tracer bullet with a mass substantially different than the normal bullet.
Furthermore, U.S. Pat. Nos. 6,497,181 and 6,990,905 teach the use of materials in tracer ammunition whereby two chemicals must mix together to provide a chemical reaction subsequent to firing or launching of the bullet thereby creating visible light. This is known as chemoluminescent material. This tracer ammunition provides a trace of the path of the projectile and also serves as a marker whereby the projectile breaks apart upon impact, scattering the chemoluminescent material. However, the use of chemoluminescent materials in tracer ammunition requires a chemical reaction wherein at least two chemoluminescent materials need to react to form at least one new compound. Such tracer rounds require an added manufacturing expense because of the need to separate the individual chemicals prior to firing. This separation of chemicals may also take up space in the bullet making it either less massive, or making the bullet longer to provide for the chemical chambers. The separation of chemicals will also make the bullet more prone to damage during handling. In addition, after firing, the two chemicals must adequately mix in order to result in the desired luminescence. Also suitable environmental conditions may be needed to allow the chemical reaction to occur. Furthermore, the chemoluminescent tracers can only be seen in flight by way of a transparent window in the bullet, which has practical constraints due to the material limitations and installation of the window.
Consequently, there remains a need for tracer projectiles that are capable of overcoming substantially all of the shortcomings of conventional incendiary and chemoluminescent tracer projectiles.